P和Al掺杂立方相Ca_2Si电子结构及光学性质的第一性原理计算（英文）  

First-principle Calculation of Electronic Structure and Optical Properties of P and Al Doped Cubic Ca_2Si

作　　者：岑伟富 杨吟野[2,4] 范梦慧[2,3] 

机构地区：[1]贵州民族大学大学生创新创业指导中心,贵阳550025 [2]贵州民族大学,贵州省教育厅光电信息分析与处理特色重点实验室,贵阳550025 [3]贵州民族大学,贵州省教育厅绿色节能材料特色重点实验室,贵阳550025 [4]贵州民族大学材料科学与工程学院,贵阳550025

出　　处：《人工晶体学报》2017年第8期1456-1463,共8页Journal of Synthetic Crystals

基　　金：Natural Science Foundation of Guizhou Province Education Department([2015]428);Science and Technology Foundation of Guizhou Province,China([2015]7218,LH[2016]7077);Youth Science and Technology Talents Growth Fund Program of Guizhou Province Education Department,China(KY[2016]166);Innovation Group Major Program of Guizhou Province(KY[2016]029)

摘　　要：采用基于密度泛函理论的第一性原理平面波超软贋势方法,分别计算了立方相Ca_2Si及掺杂P、Al的电子结构和光学性质。结果表明:立方相Ca_2Si是带隙为0.55483 eV的直接带隙半导体,价带主要由Si的3p和Ca的3d、4s态电子构成,导带主要由Ca的3d、4s和Si的3p态电子共同构成,静态介电常数为11.92474,折射率为3.45322。Ca_2Si掺P后,Ca_2Si转变为n型半导体,其带隙值是0.42808 V,价带主要由Si、Al的3p和Ca的3d、4s态电子构成,导带主要由Ca的3d、Al的3p、3s和Si的3p态电子构成。静态介电常数为7.92698,折射率为2.81549。掺Al后,Ca_2Si转变为n型半导体,带隙值是0.26317 eV,费米面附近的价带主要由Si、P的3p和Ca的3d态电子构成,导带主要由Ca的3d 4s、P的3p、3s和Si的3p态电子构成。静态介电常数为17.02409,折射率为4.12603。掺P和Al均降低Ca_2Si的反射率,提高Ca_2Si的吸收系数,提高Ca_2Si的光利用率。说明掺杂能够有效地改变Ca_2Si的电子结构和光学性质,为Ca_2Si材料的研发和应用提供理论依据。Energy band structure and optical properties of cubic Ca2Si and P（ Al）-doped Ca2Si have been calculated by density functional theory of the first-principles pseudo potential wave method. The results show that the energy band of cubic Ca2Si is a direct semiconductor with the band gap of 0. 55483 e V.The valance bands are mainly compose of Si3p and Ca3d4s,the conduction bands mainly composed of Ca3d4s and Si3p,the static dielectric function is 11. 92474,the refractive index is 3. 45322. The Pdoped cubic Ca2Si is an n-type direct semiconductor with the band gap of 0. 42808 e V. The valance bands are mainly compose of Si3p,P3p and Ca 3d 4s,the conduction bands mainly composed of Ca3 d,P3p 3s and Si3p,the static dielectric function is 7. 92698,the refractive index is 2. 81549. The Al-doped cubic Ca2Si is an n-type with the band gap of 0. 26317 e V. The valance bands are mainly compose of Si3p,Al3p and Ca3d,the conduction bands mainly compose of Ca3d4s,Al3p3s and Si3p,the static dielectric function is 17. 02409,the refractive index is 4. 12603. The reflectivity are decrease and the absorption are increase by P（ Al）-doped. The electronic structure and optical properties of Ca2Si is effectively modulate by doped,the results offer theoretical data for the experimental study of the cubic Ca2Si.

关 键 词：电子结构 光学性质 第一性原理 Ca2Si 掺杂 

分 类 号：O472.3[理学—半导体物理]